A new type of solid oxide fuel cell based on thin film technology and ultra-thin electrolyte is being proposed to develop to realize major reductions in fuel cell size, weight, and operating temperature, while significantly increasing power density. The thin film fuel cell is comprised of a micro-thin electrolyte (thickness ~ 1??m) that is grown on a foil nickel substrate. The nickel substrate is then made into a porous anode by lithographic patterning and etching of the foil. The SOFC structure is completed by the deposition of a thin-film mixed ionic-electronic conducting oxide cathode on the electrolyte. Preliminary data has shoen the thin film fuel cell to have an output of ~ 100mA/cm2 at temperatures as low as 500C more than 400C lower than for typical bulk SOFC's. A single cell has a total thickness of 15-20 micron, and the integration of interconnects to the cells to form a stack is projected to result in a cell power density of > 5W/cm3 more than 20x greater than typical SOFC's.
